Two vertical angles are given as (6x−15)° and (4x+5)°. What is the measure of each angle?

(4 Points)

35°

45°

55°

65°

1 answer

To find the measures of the two vertical angles given as \( (6x - 15)° \) and \( (4x + 5)° \), we can set the two expressions equal to each other since vertical angles are equal.

  1. Set up the equation: \[ 6x - 15 = 4x + 5 \]

  2. Solve for \( x \):

    • First, subtract \( 4x \) from both sides: \[ 6x - 4x - 15 = 5 \] \[ 2x - 15 = 5 \]

    • Next, add 15 to both sides: \[ 2x = 20 \]

    • Now, divide by 2: \[ x = 10 \]

  3. Now, substitute \( x \) back into one of the angle expressions to find the measure of the angles:

    • Using the first angle: \[ 6x - 15 = 6(10) - 15 = 60 - 15 = 45° \]

    • Using the second angle: \[ 4x + 5 = 4(10) + 5 = 40 + 5 = 45° \]

Therefore, both angles measure \( 45° \).

The measure of each angle is 45°.